diff --git a/src/day07/main.rs b/src/day07/main.rs
index 4337768..d7ec88f 100644
--- a/src/day07/main.rs
+++ b/src/day07/main.rs
@@ -76,8 +76,8 @@ impl<'a> BagRules<'a> {
 
     fn parse_bag_rule_line(line: &'a str) -> (Bag<'a>, Vec<Bag<'a>>) {
         let mut splitted = line.splitn(2, " bags contain ");
-        let key = splitted.next().unwrap();
-        let values = splitted.next().unwrap();
+        let key = splitted.next().expect("invalid bag rule line: missing key");
+        let values = splitted.next().expect("invalid bag rule line: missing value");
 
         if values == "no other bags." {
             return (key, vec![]);
@@ -85,7 +85,7 @@ impl<'a> BagRules<'a> {
 
         let values: Vec<&str> = values
             .strip_suffix(".")
-            .unwrap()
+            .expect("invalid bag rule line: not terminated with `.`")
             .split(',')
             .flat_map(BagRules::parse_bag_content)
             .collect();
@@ -99,7 +99,7 @@ impl<'a> BagRules<'a> {
         let bag = bag
             .strip_suffix(" bags")
             .or(bag.strip_suffix(" bag"))
-            .unwrap();
+            .expect("invalid bag content: no bag(s) suffix");
         let count = count.trim().parse::<usize>().unwrap();
         vec![bag.trim(); count]
     }